Subsidiary, a.
Etymology: [L. subsidiarius: cf. F. subsidiaire. See Subsidy.]
1. Furnishing aid; assisting; auxiliary; helping; tributary; especially, aiding in an inferior position or capacity; as, a subsidiary stream. Chief ruler and principal head everywhere, not suffragant and subsidiary. Florio. They constituted a useful subsidiary testimony of another state of existence. Coleridge.
2. Of or pertaining to a subsidy; constituting a subsidy; being a part of, or of the nature of, a subsidy; as, subsidiary payments to an ally. George the Second relied on his subsidiary treaties. Ld. Mahon.
1 other Webster entry under this spelling
Subsidiary, n.; pl. Subsidiaries (.
One who, or that which, contributes aid or additional supplies; an assistant; an auxiliary. Hammond.
Shades of meaning
Fernald lists subsidiary only as an antonym, under inherent.
He lists it without comment; the entries above explain its neighbors.